How To Build A Nicely Diffused Strip Light

In my kid-days from long ago, I liked to bang on things with my toy hammer and play with a pretend saw. As a kid today it is no different except that it means hot glue, Velcro, duct tape, drill bits, hack saws, wing nuts, lock washers, and so on.

My goal was to design a strip light mod for small hot shoe flashes with limited power. Instead of light-eating grids and inner diffusers found a way to use the edges of the box to cut down spill, and a reflector inside helps distribute the light more evenly. This allowed me to eliminate the inner diffuser, which soaks up the light output. I can now shoot with this strip light about 2 to 4 feet away using ¼ power!

Finally it was finished and I asked my reluctant model if she’d pose. Judy came out wearing my vest because it was cold. I really liked the pictures that came out.

I worked a solid two weeks making a light strip box for my hot shoe flash. Everyday I had to modify the experiment. It kept my mind in the photography world even though I was unable to shoot for about a month. I had to build 3 of these before I settled on a final plan. Hopefully I will be able to shorten your exploration with these directions

I can only provide you with a general notion of materials and tools. As you follow along, you will find that you must constantly rework and readjust as you go, trimming here adjusting there, adding another bolt, more Velcro, notching with a file etc. I made plenty of mistakes and to help cut down on those I remembered to always measured twice and cut once to avoid errors.

These notes are from the various experiments with a 48 inch and 30 inch strip light. I suggest you start with a smaller one first. I was na?ve enough to start with the 4 foot one. You’ll have less waste as you make mistakes.

Figure about 2 to 4 weekends as you work and rework the materials, revise and adapt these directions to suit your local materials and your flash. In the end can put a strip box with a lot of control together for about 1/3 the price of commercial. It will also be tailored to your gear.

Later in this piece I’ll provide links to the least expensive commercial alternative I know.

Build Sequance

Realistically this will probably involve 3 trips for materials you forget or run out of. I went to a place called Home Depot.

Take your largest hot shoe flash to hardware and look for interlocking down spouts that fit your flash. Gather as many materials as you can. Find out their name, cause you’ll be going back…

Build Bracket

I had to develop a bracket for my Olympus and Lumipro flash. In the right angle position they difference in height by ¾ inch. Therefore I needed two screws in the base for the hot show flash. Some of the critical features are shown in the next two images.

Measure height of flash. If you have more than 1 type, you’ll need to do what I did which is design the bracket for the shortest one, and then add a second hot shoe holder for the other one.

Bend metal. I ended up with 1-½ inch for the first bend to hold the downspout. I chose a height of 4-1/2 inches. This lead to a 5 inch long flat base. Each bend consumes ¼ inch of material and is bent in the vise, pound it at right angles with a hammer. Later you’ll have to fine-tune the angles as you try out different flashes.

To create the correct angle, I use a right angle strap. This allows the flash to be mounted on the side, with the long side parallel to the box it goes into.

Next work on the spouts that fit on the bracket and slip inside the strip box shell.

One spout goes inside the box and has flanges to angle it to the cardboard. I call this in the inner holder. The outer holder is attached to your strip metal.

Once the metal is bent and the outer holder is mounted you need to add various parts to the PVC. Small screws on the inside create a press fit. L-metal tabs are added. The coat hanger is cut off and bent to create small finger loops. This allows you to pull the box away from the bracket, without tearing the box apart.

The commercial alternative is the T-bracket and speed ring. You must get the T-bracket in order to adjust the height and depth of the flash being inserted into the strip shell. You will also need a speed ring.

Build the strip box shell

I cut it open so I can have easy access to the inside. There I create a hole for the inner holder. The flange are held in place with Velcro and also adds some rigidity around the hole. Later heavier duct tape will go over the flanges and Velcro areas.

The inside is then line with tinfoil tape and the outside where the gobo and diffuser fit are taped with black duct tape.

All other surfaces, especially seams are covered with the lighter white tape, which is generally done on the outside.

I then use Velcro to bring the ends together. This allows me to quickly open the package for easier storage. Likewise, I can narrow the sides like a barn door by bringing in the edges using other Velcro surfaces.

Outer flaps which become like gobos and taking the place of the egg-crate grid which normally goes on the front and eats up a little light as well. I can also adjust the size of the opening somewhat by moving the flaps in or out.

Lastly go along the outside of the foil and glue in some Velcro to attach the diffuser with.

Assemble outer diffuser

Wonder whatever happens to old umbrellas that crash in the wind? You re-use the “silk” or diffuser material, or you buy some from a local fabric store.

Create an outer diffuser. I measure the silk to be 1 inch larger all around. Since my big 48-inch log box is 6 x 6 I add a ½ inch to the width. That makes the diffuser is 7 inches wide and 49 inches long. I then place white tape along the end. Onto this tape I will hot glue my Velcro. The other side of the Velcro goes on the box.

I’m no seamstress and no one I knows likes to sew Velcro onto white scrim material. I run white tape along the edge, sticking out ¼ inch beyond the edge. Then I fold it back, and tape it to the other side. This creates a great surface for a base for Velcro.

Then I glue black Velcro down along the white tape seams.

Because the top and ends open up, it is easier to lay the diffuser into the box shell

The commercial alternative: trade money for time.

For those who find this DIY too challenging, the least expensive commercial alternative I found totals out (before shipping) to around $120, and won’t take 2 to 4 weekends to assemble.

The one advantage my shorter strip box has is when I place it up high for a hair light. Its short profile requires less than 15 inches, and commercial products will require significantly more.

Create a small reflector

I examined my light dispersion by looking at photo of the strip light box. With the single diffuser on, I felt the center was too hot in the center and too cool on the ends. I set about creating a reflector that would redirect the light up and down the box, knowing that a few feet away the center area of light diffusion would get filled in. This uses the same principle as a DIY beauty dish.

It was so successful I later put this in my commercial strip light and was able to eliminate the inner diffuser.

Begin by laying out a pattern than equals the rectangular shape ands size of your flash head. Then add some sides. For my flashes it looks like the following

Tape together the bottom to form a pyramid. You can skip the tape if you have 3 hands.

Then tape the side, angled down.

roll tin foil tape over side facet…then you may have to trim the opposite facet so it will fold down.

Completely assembled, velcrow this in on the outter diffuser. Place on the inside, center. Remember to orient it so the vertical placed flash has the light directed to the far ends as you see next.

MAKE FINAL ADJUSTMENTS AND THEN PAINT IT BLACK

When using the a lighter strip light say 30 inches or shorter, you can get by with press fit on the PVC pipe. However, when you place it above a subject for a hair light I strongly advice securing the connection between the shell and bracket by using a bolt and wing nut on both sides. This is illustrated next.

Final assembly prior to being painted black. Photo shows the flash mounted on stand.

Shots With Jene Rene

In this shot I use my 30-inch DIY for a hair light (camera right, above and behind) and then added the 48 inch commercial strip light on camera left. Then I swapped out the commercial for the DIY. Both yield wonderfully soft and continuous light.

The light fills in nicely up and down, including a face under hat brim

About The Author

Martin Kimeldorf is a photographer, maker and baker. You can follow his work on his flickr stream here and learn about his green screen techniques here.

John Aldred is a portrait and animal photographer in Lancaster, England. you can see some of his work on his website, or find him on Facebook or Twitter.

Stefan Kohler is a conceptual photographer, specialized in mixing science, technology and photography. He is one of the founders of Kamerakind, based in Traunstein, Southern Germany. You can follow him on Facebook or on 500px.com

Liron Samuels is a wildlife and commercial photographer based in Israel.

When he isn't waking up at 4am to take photos of nature, he stays awake until 4am taking photos of the night skies or time lapses.